Circuit-breaker



A. SIMON.

CIRCUIT BREAKER.

APPLICATION FILED JULY 29,19I6.

1,330,094. Patented Feb. 10,1920. v

INVENTOR.

' tapered at its lower end to cooperate with a V UNITED STATES PATENT orrro.

ARTHUR sIMON, or MILWAUKEE, WISCONSIN, ASSIGNOR TO THE CUTLER-HAMMER MFG. 00., or MILWAUKEE, wIsooNsIN, A CORPORATION OF wIsooNsIN.

CIRCUIT-BREAKER.

To all whom it may concern: Be it known that I, ARTHUR SIMON, a c1t1- zen of the United States, residing at Mil-- w-aukee, in the county of Milwaukee and State of Wisconsin, have invented new and useful Improvements in Circuit-Breakers, of which the following is a full, clear, conc1se, and exact description, reference being had to the accompanying drawing, forming a part of this specification.

This invention relates and more particularly to those of the combined time element andinstantaneous type. The invention has among its objects to provide a'simple'and eflicient circuit breaker having a retarded response to overloads up to a predetermined value and a substantially instantaneous response tooverloads in excess of such-value. p

Other objects will hereinafter appear.

In the accompanying drawing, wherein 1s illustrated an embodiment of the invention,

Figure 1 is a side elevation view, partly in section, of a circuit breaker constructed in accordance therewith ;and,

Fig. 2 is a similar view of a modlfied construction.

' Referring to Fig. 1 of the drawing, the

circuit breaker comprises a switch 1 arranged to be engaged and tripped by a lever. 2, which latter is actuated by an overload solenoid 3. The degree of overload at which the solenoid responds is determinable by an adjustable weight 4 upon the said lever and. the solenoid in responding is retarded by a dash p'ot 5 having a piston 6 operating therein, the latter being connected to the lower end of solenoid plunger 7. A bypass 8 having an adjustable plug valve 9 serves to determine the rate of descent of the piston 6 thereby fixing the. time element of the circuit breaker.

The plunger 7 is constructed hollow and is flat faced magnetic plug 10 at the lower end of solenoid 3. This construction provides a relatively flat pull curve characteristic near the beginning of the stroke and'a relatively steep characteristic near the end thereof,

to circuit, breakers portion of the plunger stroke of dash pot retardation. The piston 6 is provided with a downwardly opening valve 11 which serves to relieve the plunger 6 of dash pot retardationduring upward movement thereof.

Specification of Letters Patent. Patented Feb, 10, 19,20, Application filed July 29, 1916. Serial NO. 111,990. I

The above described arrangement of parts is substantially identical with that of my co-pending application Serial No. 99,038, filed May 22, 1916.

For enabling an immediate response of 7 the above described circuit breaker to overloads exceeding a predetermined value a yielding connection is provided between the plunger 7 and the piston 6. This connection includes a rod 12 having a head 13 slidingly fitted within the lower portion of the hollow plunger 7, the head 13 being retained therein by a cooperating shoulder. A helical spring 14c is inclosed within said hollow plunger with its lower end resting upon the head 13'of the rod 12, while its upper end engages a plug 15 screw threaded within the, upper end of said plunger. The plunger is connected with the lever 2 by means of a link 16 and pins 17.

During overloads not exceeding a predetermined value, the Operation of the circuit breaker is in no wise afi'ected by the elements last described. However, upon the occurrence of an Overload in excess of such value,

'rise under the influence of the spring 14:

until the head of the rod engagesthe contracted shoulder at the lower end of the plunger bore, following which the plunger the weight 4, which relation of parts is sus' tained until the occurrence of a subsequent overload. I

The sensitiveness of the above described parts for instantaneous response may be varied by screwing down the plug 15 within the hollow plunger for which purpose a key slot is provided in the upper face of said plug. Obviously this adjustment might be otherwise accomplished.

Referring now to Fig. 2 of the drawing, the parts constituting the time element circuit breaker are substantially identical with those above described. The parts for producing an immediate response, however, have been modified. In this construction a magnetic bar 18 hingedly mounted at 19 upon the lower leg of solenoid frame 20 for attraction toward the upper leg of said frame. The upper end of said bar 18 is provided with an insulating projecting portion 21 for engaging and tripping the switch arm 22 upon attraction of said bar. An arm 23, preferably integral with the bar 18, projects at an angle from the lower end thereof and is' provided with an adjustable weight 24 which biases the said bar to stand in open up'onthe occurrence of an overload exceeding a certain value the magnet bar 18 is forcibly drawn toward the magnet frame 20 against the action of its biasing means, whereby circuit is interrupted practically instantaneously through the tripping of switch 1. Following circuit interruption in the manner above described, the bar 18 is free to respond to its biasing means whereupon the switch 1 is 'free to resumenorma]. position, as illustrated.

The sensitiveness of the above described circuit interrupting means for instantaneous response may be varied by shifting the weight 24 along the arm 23. A similar result may be attained by adjustment of the screw 25 which serves to vary the length of the air gap between the free end of the magnet bar 18 and the magnetic frame 20. It may be noted, however, in this connection that adjustment of the said screw furthermore operates to vary the calibration of the entire circuit breaker, including the time element portions thereof, since by variations of the air gap the reluctance of the entire magnet is altered.

What I claim as new and desire to by Letters Patent is:

1. In combination, a switch, an overload winding, and means operable by said winding to trip said switch immediately under given overload, conditions and subject to a given delay under certain other overload conditions, said means including a plunger for said winding subjected to a substantially uniform pull during the major portion of its stroke and an augmented final pull and retarding means for said plunger adapted to release the same substantially at the initiation of said augmented final pull.

2. In combination, a switch, an overload winding, means operable by said winding to trip said switch immediately under given overload conditions and subject to a given delay under certain other overload conditions, said means including a plunger for said winding subjected to a substantially uniform pull during the major portion of its stroke and an augmented final pull and retarding means for said plunger adapted to release the same substantially at the initiation of said augmented final pull, and means for varying the sensitiveness of response of said tripping means.

3. In combination, a switch, an overload winding, means operable by said winding to trip said switch immediately under given overload conditions and subject to a given delay under certain other overload conditions, said means including a plunger for said winding subjected to a substantially uniform pull during the major portion of its stroke and an augmented final'pull and retarding means for said plunger adapted to release the samesubstantially at the initiation of said augmented final pull, and means secure for adjusting said tripping means for variation of the sensitiveness of response thereof either for delayed or immediate tripping of said switch.

4. In a circuit breaker, in combination, a sWitch,-tripping meanstherefor including an electromagnetic windin and a plurality of movable magnetic mem ers to be attracted thereby for tripping said switch immediately or subject to a given delay selectively upon energization of said -winding to predetermined diiferent degrees, and means for adjusting one of said magnetic members relas tively to said winding for variation of the sensitiveness of response of the former.

5. In a circuit breaker, in combination, a switch, tripping means therefor including a solenoid winding, a pair of magnetic members to' be attracted through energization of said winding, means for adjusting one of said magnetic members relative to said windtaininga given relation between said magnetlc members and sald wlndlng.

6. In a circult breaker, 1n comblnatlon, a

switch, tripping means therefor including a solenoid winding, a pair of magnetic mem- .bersto be attracted through energization of of either.

said Winding, means for adjusting one of said magnetic members relatively to said Winding and means for varying the sensitiveness of response of eaeh of said magnetic members without varying the position In witness whereof, I have hereunto subscribed my name.

ARTHUR SIMON. 

